Gun-charging mechanism



sepa. 24,v 1946.

F. R, THRr-:sH

GUN-CHARGING MECHANISM Filed July l0, v1944 3 Sheets-Sheet 2 Sept. 24,i946. F. R. THRESH GUN-CHARGING MECHANISM Filed July 1o, 1944 svsheets-sheet -3 [n/enfar Patented Sept. 24, 1946 Agai- GUN- CHARGINGMECHANISM Frank R. Thresh, Beverly, Mass., assignor to United ShoeMachinery Corporatiom' Flemington, N. J., a corporation of New JerseyApplication July 10, 1944, Serial No. 544,207

15 Claims.

This invention relates to mechanism by which a machine-gun may becharged or cocked by the operator, if vthe normal discharge fails toload the counter-recoil-spring ready for the firing of the succeedinground. It is especially applicable to the charging of guns demanding anal)- plication of a relatively large force. Y The invention has as anobject the minimizing the effort which the operator must exert incharging the gun, and the simplifying the manipulation of the mechanism.In the attainment of this object, I combine with a gun and thecounter-recoil-spring ci its breech mechanism, means for applying to thespring a lo-ading force, and means for increasing the applied force asthe loading of the spring progresses. This force, exerted by theoperator of the gun, is transmitted to the spring-through a lever-arm,which decreases in its effective length as the spring is loaded, andthus increases the leverage in favor of the operator as thespring-resistance increases. This decrease in the length of-thelever-arm is preferably obtained by providing it with a portion ofdecreasing radius, and connecting the gun to a portion of the arm ofgreater radius by a exible member which contacts With the decreasingportion during movement of the arm. To make it possible for the operatorto charge the gun by successive actuations of the lever, ratchetmechanism is interposed between the operator-actuated means and theforce-increasing means. To facilitate connection of the chargingmechanism to the gun, there may be means for rendering the ratchetmechanism effective or ineffective. When it is desired to advance thenormally retracted connecting member for attachment to the gun, acontrolling member movable by the operator renders the ratchet mechanismineffective. so the advance is permitted. This controlling member may bemoved in the advance of the connecting member for attachment to the gun,to again make the ratchet mechanism effective. The member which isconnected to the gun, as to the breech-bolt, for transmittinor theretothe charging force, must be disconnected before the discharge of thegun. This I accomplish by means made active during the loading of thecounter-recoil-spring, said means acting upon the connecting memberafter the spring has been loaded. The breech-bolt over-travels in itscharging movement, and during the return from over-travel thedisconnection and positioning of the member is produced Without specialattention on the part of the operator.

Considering the charging mechanism itself, it has an arm movable by theoperator, and a second arm to which is joinedy aV flexible connectingmember, as a chain, it contacting during the charging operation with anarm-portion of gradually decreasing radius. The first arm may beoscillated about a shaft and carries a pawl for engagement with aratchet-wheel -fast upon the shaft. The second arm, tol whicntheiiexible member is joined, isv iixedtothe shaft, and"V is thus moved insuccessive steps by the oscillation of the rst arm. The engagement ofthe pawl with the ratchet-wheel, and also that of a retaining detent forsaid Wheel, is controlled by an oscillatory member or plate providedwith projections for engagement with the pawl and detent. This membermay be shifted between positions in which its -projections are inactiveor active, this being accomplished by the operator and bytheratchet-wheel, it being releasably latched in each position. Theflexible member has a connecting terminal, and means acting upon the armto which it is joined draws thel terminal against a stop member, so itis ready to be advanced by the operator for connection to the gun andagain retracted to its initial position after such use. There is meansengaging this terminal for disconnecting it from the gun, which meansmay be in the form of a movable member lor lever, also furnishing thestop.- which is urged toward the terminal by a spring while anotherspring, as that by which the flexible member is retracted, urges theterminal into engagement with the lever in a predetermined angularposition. During the final stage of the charging action, thelever-spring is energized and, being stronger than the terminal-spring,overcomes this to apply to the terminal the disconnecting movement. Inthe accompanying drawings, Fig. 1 shows my improved charging mechanismin side elevation, with itsV operating treadle and connected to a gun;

Fig. 2 is a perspective view of the charging mechanism broken away andportions displaced laterally;

Fig. 3, a front elevation of the mechanism viewed from the right in Fig.1; Y

Fig. 4, an enlarged partial side elevation, of the charging mechanism; rFig. 5, a transverse sectional detail, showing the controlling cam-platefor the pawl and detent ofthe ratchet mechanism; l

Fig. 6, a similar view of the chain-retracting spring; and l 1 Figs. 7and 8, details in perspective of the means for retracting, respectively,the detent and pawl of the ratchet mechanism.

f There appears at T a portion of the side of a turret, from whichprojects a hood I-I in which a gun G is housed. This gun may be of theOerliken type, upon the breech-casing i of which may be seen portions ofthe breech-bars i2, i2 and of the counter-recoil-spring I4 by which thebreech-bolt is urged forward for the ring of a cartridge after thedischarge of the preceding round. If this discharge, for any reason,does not occur, it is necessary to apply to a catchplate or stud I6 uponone of the breech-bars an external force to compress thecounter-recoilspring, until it is latched by the breech-pawls ready forfiring. In the gun under consideration, the spring I4 holds thebreech-boltV closed and is necessarily very strong, requiring a heavyforce to compress it. The mechanism by which the spring is loaded andthe gun charged ready for firing appears at C.

Secured to the top of the hood I-I is a bracket 20, provided with spaceddepending arms 22 and 24. In bushings 26 and 23 in said arms a shaft 30is rotatable, it having secured to it a ratchetwheel 32. Mounted tooscillate upon the inner end of the shaft, retained in place by a screwand Washer 34 (Fig. 3), is'an arm 35 having at its outer side aprojection 31, upon which is pivoted a pawl 38 engaging the teeth of theratchet- Wheel. A tension-spring 40, extending between projections fromthe arm and pawl, yieldably maintains such engagement. From the end ofthe arm, a link 42 extends within the turret to an arm of abell-crank-lever 44 fulcrumed on a spindle 45 extending between theturret-walls. The long arm 46 of the lever carries arest 48, convenientto receive contact of the foot of the man `within the turret servicingthe guns. This treadle mechanism may act upon the charging mechanisms ofguns at opposite sides of the turret, there being one of thebell-crank-levers fulcrumed upon each end of the spindle 45. Thelever-arm 46 is held yieldably toward the rear by a tension-spring 50,joining the lever to the turret-wall. Repeated actuation of the leveragainst the force of the spring will cause the pawl 38 to turn theratchet-wheel in successive steps, where it is retained, until released,by a detent 52 pivoted upon the wall of the turret and urged intoengagement with the ratchetteeth by a tension-spring 54 connecting it tosaid wall. The pawl 38 and the detent 52, in their engagement with theteeth of the ratchet-wheel, may be controlled simultaneously by acam-plate 56, rotatable upon the end of the bushing 26 at the inner sideof the bracket-arm 22. Projections 58 and 60 upon the plate engage pinsS2 and 64 set in the pawl and detent, respectively. The cam-plate may beturned by a finger-piece 56 to position the projections in theirineiective relation, with the paWl and detent free to act upon theratchet-wheel. In the opposite direction, the plate is shiftedautomatically, as will hereinafter appear. In its two positions, theplate may be latched by a spring-plunger 88 mounted in the bracket-arm22 and engaging either a depression or 'I2 in the edge of the plate.Oscillation of the plate in both directions is limited, and registrationof the depressions iii and 12 with the plunger 63 established, by astoppin 14 projecting from the bracket-arm 22 through an arcuate slot 76in the plate.

On the other end of the shaft 30 from the ratchet mechanism is fixed anarm 18, having a curved edge 80 of gradually increasing radius. To thearm, at or near the point of maximum radius, is attached a chain 82,which is led rearwardly over a guide-roll 84 rotatable upon the outerextremity of a bracket 86, projecting horizontally from the wall of theturret T beneath the bracket 20. The free end of the chain carries aterminal loop 88, the opening of which is adapted to receive thebreech-bar-stud I6 when the gun G is to be charged by the mechanism C. Aconstant force is exerted upon the chain, tending to retract the loop,by a spiral spring 90 surrounding the shaft 30. The outerend of thespring is connected at 92 to the arm 13, while the inner end is angularand may be inserted in any one of a plurality of notches 94 (Fig. 6) ina boss upon the bracket-arm 24. The latter connection permits thetension of the spring to be varied. In advance of the roll 84, the chain82 is supported by a laterally projecting shoulder 36 from a stationaryarm 98 attached to the end of the bracket 86. To determine the normallocation of the loop 88, shoulders |00, |00 upon the inner end are drawnby the spring 90 into engagement with the lower bifurcated extremity ofa lever |04 fulcrumed upon the end of the bracket 85 and having hookedend-portions |02, |02. This engagement with the lever is just above thehooks, which are urged forward by a tension-spring |05, joining theupper extremity of the lever to the bracket 86 and holding it yieldablyagainst a stop-pin |08 set in the bracket (Fig. 2). The spring |06exerts upon the leverends |02 a greater force to advance them, than doesthe spring 90 through the chain |02 to retract them. As the spring 90brings the loopshoulders |00 against the lever, the contact is firstmade by angular ends |01. Then the continuing pull of the spring causesthe loop to pivot about itsr connection to the chain at |05, drawinginclined walls |09 upon the shoulders against the generally verticaledges of the lever. The loop is now in a predetermined angular position,inclined upwardly from the horizontal, out of the path of thefbreech-bolt-stud.

A gun G in the turret having jammed, the man servicing the guns firstactuates the cam-plate of the charging mechanism C for that g-un by `theinger-piece to shift it counterclockwise (Fig. 5). This carries it fromthe inactive position, where it was left after the preceding operationwith the plunger E0 en-gaging the plate-depression l2, to the activerelation in which the plunger is in the depression l0. The projections58 and 60 of the plate lift both the pawl 38 and the detent 52 from theratchet-wheel 32, leaving this free to turn clockwise (Fig. 2). Then,the loop 88 of the charging mechanism is taken and drawn forward, untilit can be placed over the breech-bolt-stud Hi, which is in the forwardposition appearing in full lines at a in Fig. l. The pull of the springSi) upon the chain places this under sufficient tension to take up theIslack and maintain the lo-Op in secure engagement with the stud. J ustbefore the loop arrived at the forward point, a projection H0 from thehub of the ratchet-wheel struck a pin H2 projecting inwardly from thecam-plate 55. The movement of the plate thus produced is sufcient toturn it clockwise, until the plunger 63 occupies the depression 12 andthe cam-projections free the pawl and detent, so these again engage theteeth of the ratchet-wheel. The bell-crank-lever 44 may now beoscillated successively by the combined effect of the foot of theoperator and of the spring 5l), causing the pawl 38 to impart to theratchetwheel a series of steps, at the end of each of which it is heldagainst recession by the detent 52. This turns the arm l8 in thedirection of the arrow, drawing-upon the chain 82 to retract graduallythe breech-bolt of the gun. In addition to the constant advantageobtained by the operator through the leverage of the bell-crank-leverand of the mechanism C, there is an increase in leverage at lsaidmechanism as the compressing of the counter-recoil-spring I4 progressesand the resistance to such compression increases. This is obtainedWithout a corresponding increase in the extent of foot-movement, due tothe gradual shortening of the work-arm Z8 of this lever system, ascompared with the power-arm 35 as the radius of the curved edge Si!decreases at the leading point of contact with the chain. Thus, theeffort required of the operator is more nearly uniform through thecharging of the gun.

When the stud I6 has been drawn back to the position indicated in dottedlines at b (Fig. 1), the :full recoil-movement of the breech-bolt hasbeen produced, and the breech-pawls have become eiective. However, thebreech-bolt of the gun has not reached the limit of rearward movement,so there is an over-travel of the chain. During this over-travel, theshoulders move in engagement with the lever Hill, swinging thisclockwise (Fig. 2) until completion of retraction of thebreech-boltstops the chain with the stud I6 at c. The operator, Vfeelingthis, allows the spring 50 to retract the treadle. During the movementof the breech-bolt-stud between positions c and b, the spring 99 drawsback upon the chain-loop 88, but'the spring |86, being stronger than thespring Se, abruptly urge-S the` hooked ends |02 of the lever |94counterclockwise. Just as the Istud arrives at position b, where thebreechbolt is latchedand the chain is relieved of the pull of thecounter-recoil-spring, inclined surfaces ||4 of the hooks, acting uponcomplementally inclined surfaces llt of the shoulders mi), cam up theloop sharply and disengage it from the stud I6. This leaves thebreech-bolt latched by its pawls, freed from the chain ready for thedischarge of the gun. The loop-shoulders are carried by the spring yil!!to their normal positions against the end of the lever, with the loopraised about the stud, as already described. During .this stud-freeingmovement of the loop and chain, the detent 52 rests upon a peripheralportion |18 of the ratchet-Wheel, which is without teeth and does notinterfere with the action of the lever |85 as the stud and loop travelfrom c to b.

The operator may wish to utilize the mechanism C for removing the loadfrom the counterrecoil-spring i4 of the gun. For convenience in thisconnection, means may be provided for retracting both the pawl 38 andthe detent 52 from the teeth of the ratchet-wheel 32. As shown in Fig.8, there is rotatable in the arm-projection 3l a shaft |25, having inprom'mity to the inner side of the pawl a cam-portion |22; At theopposite extremity of the shaft, within the turret T, is a finger-piece|24. The normal position of the cam is such that it permits the pawl toengage the ratchet-teeth. It may, however, be rotated by thefinger-piece to bring into contact with the pawl a portion of the cam ofgreater diameter, thus separating said pawl from the teeth. Similarly,as is best shown in Fig. 7, a shaft |26 with its cam |28 andfinger-piece |30 turns in the turret-wall, so the cam may act upon thedetent 52. These two devices may be used in the following manner. Withthe chain-terminal 88 applied to the breech-'bolt-stud I6, the operatoractuates the finger-piece |24 to remove the pawl 38 from theratchet-teeth, and then advances the foot-rest 48 to its extreme point.The spring 5B is thereupon allowed to retract the lever-arm 46 throughashort distance, and the finger-piece is freed sorthat the pawlre-engages the ratchet- Wheel, which is being held against the force ofthe counter-recoil-spring by the detent 52. From this position thefoot-rest is again operated through its limited forward movement torelieve the detent from the pressure of the spring, and said detent isseparated from the ratchet-Wheel by operating the finger-piece |30, Thefoot-rest may now lbe allowed to travel fully to the rear, the force ofthe spring thereby .being reduced. 'Ihe finger-piece |30 is released sothe detent again engages the ratchet-Wheel, the finger-piece |24 isactuated as before, and the foot-rest returned idly to its forwardposition. There follows the alternate relief of pressure upon the detenta nd its separation from the ratchet-wheel, release of compression ofthe counter-recoilspring during rearward travel of the foot-rest, andrei-engagement of the detent, retraction of the pawl and forward travelof the foot-rest, untilV the spring is unloaded to the desired degree.

Having described my invention, what I claim as new and desire to secureby Letters Patent of the United States is:

l. In combination, a gun including breech mechanism andafcounter-recoil-spring therefor, and means for actuation by an operatorto apply to the spring a loading force, said means comprising means forincreasing the appliedforce as the loading of the spring progresses andratchet mechanism transmitting the applied force to the force-increasingmeans.

2. In combination, a gun including breech mechanism and acounter-recoil-spring therefor, and means for actuation by an operatorto apply to the spring a loading force, said means comprising means forincreasing the applied force as the loading of the spring progresses,ratchet mechanism transmitting the applied force to the forceincreasingmeans and means for rendering the ratchet :mechanism eiective orineifective for the transmission of the charging force.

3. In combination, a gun including breech mechanism and acounter-recoil-spring therefor, and means for actuation by an operatorto apply to the spring a loading force, said means comprising ratchetmechanism transmitting the applied force to the spring, a normallyretracted connecting member which may be advanced by the ratchetmechanism for the application of the charging forceto the spring, amember movable by the operator to render the ratchet mechanismineifective for the transmission of the charging force and means actingin the advance of the connecting member to render said ratchet mechanismeffective for the transmission of the charging force.

4. Mechanism for charging a gun including breech mechanism, saidcharging mechanism comp-rising an arm movable by an operator, a secondarm connected for movement by the rst and having a portion of decreasingradius, and a ilexible member arranged for connection to the breechmechanism and joined to a portion of the second arm of greater radius,said member contacting with the decreasing portion of the second armduring its gun-charging movement and receiving therefrom an increasingcharging force.

5. Mechanism. for charging a gun including breech mechanism, saidcharging mechanism comprising a shaft, an arm for actuation by anoperator to turn the shaft, an arm fixed to the shaft and having an edgedecreasing in radius from a maximum, and a flexible member joined to thearm having an edge decreasing in radius at its maximum radius andcontacting with its edge, said member lbeing arranged for connection tothe breech mechanism and applying thereto an increasing charging force.I

6. Gun-charging mechanism comprising a shaft, an arm` arranged tooscillate Vabout the shaft, a ratchet-wheel fast upon the shaft, a pawlcarried by the arm for engagement with the ratchet-wheel, a second armxed to the shaft and having an edge decreasing in radius from a maximum,and a flexible member joined to Y the second arm at its maximum radiusand contacting with its edge, said member, being arranged for connectionto a gun.

"7. Gun-charging mechanism comprising a shaft, an arm arranged tooscillate about the shaft, a. ratchet-wheel fast upon the shaft, a pawlcarried by the* arm for engagement with the ratchet-wheel, a detent forretaining the ratchetwheel in the positionV to which it has beenadvanced by the paWl, an oscillatory member provided with projectionsfor engagement with the vpawl and detent, a second arm fixed to theshaft,

and a flexible member joined to the second arm and arranged forconnection to a gun.

8. Gun-charging mechanism comprising a shaft, an arm arranged tooscillate about the shaft, a ratchet-wheel fast upon the shaft, a pawlcarried by the arm for engagement with the ratchet-wheel, a detent forretaining the ratchetwheel in the position to which itihas been advancedby the pawl, an cscillatoryrmember provided with projections forengagement with the pawl and detent, means carried by the ratchetwheelfor shifting the oscillatory member, a second arm fixed to the shaft,and a flexible member joined to the second arm and arranged forconnection to a gun.

9. Gun-charging mechanism comprising a shaft, an arm arranged tooscillate about the shaft, a ratchet-wheel fast upon the shaft, a pawlcarried by the arm for engagement with the ratchet-Wheel, a detent forretaining the ratchetwheel in the position to which it has been advancedby the pawl, a plate having a finger-piece mounted to turn about theshaft and provided with projections for engagement with the paWl anddetent and with depressions corresponding to the projections, a latchfor engagement with either of the depressions, means whereby theratchet-wheel may turn the plate to a latched position in which the pawland detent are freed from the plate-projections for engagement with theratchet-wheel, movement of the plate by the finger-piece causing it tobe latched with the plate-projections engaging the pawl and detent tolift them from the ratchet-wheel, a second arm fixed to the shaft, and afiexible member joined to the second arm and arranged for connection toa gun.

10. Mechanism for charging a gun including breech mechanism, saidcharging mechanism comprising a shaft rotatable by an operator, an armfixed to the shaft, a flexible member joined to the arm and providedwith a terminal for connection to the breech mechanism, a stop member,and means acting upon the arm to draw the terminal into engagement withthe stop member in a predetermined relation to the breech mechanism.

11. Mechanism for charging a gun including breech mechanism, saidcharging mechanism comprising a shaft rotatable by an operator, an armfixed to the shaft, a flexible member joined to the arm and providedwith a terminal for connection to the breech mechanism, and meansengaging the terminal to disconnect it from the gun upon thev completionof the charging operation.

12. Mechanism for charging a gun-including breech mechanism, saidcharging mechanism comprising a shaft rotatable by an operator, an armfixed. to the shaft, a flexible member joined to the arm and providedwith a terminal for connection to the breech mechanism, a movable stopmember with which the terminal contacts, and means for moving the stopYmember to disconnect the terminal from the gun upon the completion ofthe charging operation.

13. Mechanism for charging a gun including breech mechanism, saidcharging mechanism comprising a shaft rotatable by an operator, an armfixed to the shaft, a flexible member joined to the arm and providedwith a terminal for connection to the breech mechanism, a lever having aportion with which the' terminal contacts, a spring urging saidlever-portion toward the terminal and being tensioned during thecharging of the gun, and a spring urging said terminal into engagementwith said iever-portion, the leverspring being the stronger of the twosprings and acting upon the lever to free the terminal from the breechmechanism.

14. Mechanism for charging a gun including breech mechanism, saidcharging mechanism comprising a shaft rotatable by an operator, an armfixed to the shaft, a flexible member joined to the arm and providedwith a terminal for connection to the breech mechanism, a lever having ahooked end, means for urging the hooked end forwardly and upwardly, andmeans including the arm and the flexible member for drawing the terminalagainst the lever for movement by the hooked end.

15. In combination, a gun including breech mechanism and acounter-recoil-spring therefor, means for applying to the spring aloading force, said means including a member mounted independently ofthe gun and arranged for actuation by an operator and a second memberthrough which the force exerted by the operator on said first member istransmitted to the spring, said second member being arranged for manualtransfer by the operator from an inactive position to active connectionto the breech mechanism, and means made effective during the loading ofthe spring for acting upon the second member to disconnect it from thebreech mechanism and return it to its inactive position.

FRANK R. THRESH.

